Interior of the Chin Chin Restaurant, the subject of a lawsuit from a former employee. Photo: Michael Hicks

Kitchen workers at a celeb-packed Manhattan Chinese restaurant allegedly use a culinary technique they don’t teach at Le Cordon Bleu — making mock penises out of the dumplings before serving them to diners, an ex-bartender claims in a lawsuit filed yesterday.

Yvonne Diaz says the disgusting displays were but one item on a menu of sexual harassment and assault that she endured while working at Chin Chin on the East Side between 2007 and last October.

Diaz claims the workers at the eatery — which boasts customers such as Tyra Banks and Jennifer Lopez — routinely used dumplings to make nasty food phalluses, putting them “in their crotch areas making it look like they had big penises.”

The dirty dumplings would then wind up on unsuspecting customers’ tables, Diaz claimed.

“Kitchen employees would with no hesitation prepare food to be served to the customers from the very same dumplings that they used to make penises,” the suit says.

Diaz also alleges that owner Jimmy Chin boasted of overcharging Sean “Diddy” Combs for a bathroom mirror that got broken during a back-room taping of his show “Making the Band,” according to the Manhattan federal court filing.

And Chin — who she said occasionally used racist terms — once said it was “a good decision” to put Mariah Carey in a “private section” after she showed up “high on drugs,” court papers say.

Diaz’s suit, which seeks unspecified damages, says she was repeatedly ogled and harassed by porn-loving co-workers who watched X-rated movies in the kitchen every Sunday “without exception.”

At least once a month, she says, some of the kitchen workers would approach her while holding a pair of oranges to their chests and saying: “Nay Nays; Nay Nays is very good.”

Diaz also alleges she was repeatedly groped by at least two co-workers, one of whom “pushed his erected penis into [her] buttocks area.”